The remaining 25 animals on this program that were exposed to either 5000 rad from Radium-226 or 800 rad from Californium-252 will be necropsied. The organs that are at risk in radiotherapy for cervical cancer from these animals along with those from 25 animals killed during the 05 period will be sectioned and studied for radiation injury. The results will be combined with those from about 50 swine exposed to higher doses from both 226Ra and 252CF to obtain a fairly complete picture of the dose response of the rectum and urinary tract to photons and neutrons. An RBE (Relative Biologic Effectiveness) factor will be provided in those important organs and that factor may be used by a radiotherapist to prescribe a dose from 252Cf that is safe to adjacent normal tissue and which may be used for treating a cervical tumor.